Automated brick laying system for constructing a building from a plurality of bricks

ABSTRACT

An automated brick laying system ( 10 ) for constructing a building from a plurality of bricks ( 16 ) comprises a robot ( 12 ) provided with a brick laying and adhesive applying head ( 18 ), a measuring system ( 13 ), and a controller ( 14 ) that provides control data to the robot ( 12 ) to lay the bricks ( 16 ) at predetermined locations. The measuring system ( 13 ) measures in real time the position of the head ( 18 ) and produces position data for the controller ( 14 ). The controller ( 14 ) produces control data on the basis of a comparison between the position data and a predetermined or pre-programmed position of the head ( 18 ) to lay a brick ( 16 ) at a predetermined position for the building under construction. The controller ( 14 ) can control the robot ( 12 ) to construct the building in a course by course manner where the bricks ( 16 ) are laid sequentially at their respective predetermined positions and where a complete course of bricks for the entire building is laid prior to laying of the brick for the next course.

FIELD OF THE INVENTION

The present invention relates to an automated brick laying system forconstructing a building from a plurality of bricks.

BACKGROUND OF THE INVENTION

The general idea or concept of attempting to automate the constructionof a building by use of an automated or semi-automated device such as aprogrammable robot is known and is the subject of numerous prior patentsand patent applications. Examples of such patents and patentapplications include U.S. Pat. No. 3,950,914 (Lowen), U.S. Pat. No.4,245,451 (Taylor-Smith) and DE 19600006 (Bachau), U.S. Pat. No.5,018,923 (Melan), WO 2004/083540 (Steenberg) and EP 836664 (Markel).

The above documents show various aspects of known automated or roboticbrick laying methods and apparatus. Some documents concentrate onspecific structure of a mechanism for gripping a brick. Other documentsrelate to building brick structures on a wall by wall basis either insitu or offsite to be transported to a location where a building is tobe constructed.

It is to be understood that, if any prior art publication is referred toherein, such reference does not constitute an admission that thepublication forms a part of the common general knowledge in the art, inAustralia or any other country.

In the claims of this application and in the description of theinvention, except where the context requires otherwise due to expresslanguage or necessary implication, the words “comprise” or variationssuch as “comprises” or “comprising” are used in an inclusive sense, i.e.to specify the presence of the stated features but not to preclude thepresence or addition of further features in various embodiments of theinvention.

Throughout this specification the term “brick” is intended to denote anytype of brick or block from which a building can be constructed.Typically this will include masonry, concrete or mud bricks or blocksfrom which a building or similar structure can be constructed. Howeverthe specific material from which the brick or block is made is notcritical to the present invention and embodiments of the invention maybe applied to bricks or blocks made from other materials such asrefractory materials, plastics materials or wood.

Throughout this specification the term “adhesive” is used to denote anycompound, mixture, chemical, or settable material that is, or can be,used to adhere two or more bricks as hereinabove defined together. Whenthe bricks are masonry bricks, typically the adhesive will be mortar.

SUMMARY OF THE INVENTION

According to one aspect of the present invention there is provided anautomated brick laying system for construction a building from aplurality of bricks comprising:

-   -   a brick laying robot provided with a moveable support structure        and a brick laying and adhesive applying head coupled to an end        of the moveable support structure the head comprising at least        one manipulator operable to lay bricks;    -   a measurement system which measures the position in real time of        the head and produces corresponding position data; and,    -   a controller which receives the position data and produces        control data on the basis of a comparison between the position        data and a stored predetermined position for the head to lay a        brick a predetermined location for the building, the controller        controlling the moveable support structure to provide coarse        positioning of the head and controlling the or each manipulator        to provide fine positioning of the bricks.

The measurement system may comprise an inertial navigation system thatprovides data relating to the location in space of the head that is usedby the measurement system to produce the position data.

The measurement system may further comprise a scanning laser to providefurther location data relating to the real time position of a brick heldby the head, wherein the measurement system uses the further locationdata to produce the position data.

According to a second aspect of the present invention there is providedan automated brick laying system for constructing a building from aplurality of bricks comprising:

-   -   a brick laying robot provided with a brick laying and adhesive        applying head;    -   a measurement system which measures the position in real time of        the head and produces corresponding position data; and    -   a controller which received the position data and produces        control data on the basis of a comparison between the position        data and a stored predetermined position for the head to lay a        brick a predetermined location for the building, the controller        controlling the robot to lay the bricks at their respective        predetermined locations in a sequence where a complete course of        bricks is laid prior to the laying of a brick for a next course        of bricks.

The robot may comprise a movable support structure on which the head issupported and the controller controls motion and position of the supportstructure and the head on the basis of the control data. The robot mayfurther comprise a ground engaging base to which the support structureis coupled, and wherein the controller controls the position of thebase. More particularly, the controller controls the position of thebase to maintain the position of the head in a datum plane for aparticular course being laid. Depending on the type of base, the controlexerted may be manifested by the deployment of one or more jacks on thebase to counteract a bending or twisting moment applied by the supportstructure to the base.

In one embodiment the head comprises at least one manipulator arrangedto grip and lay a brick at its predetermined location and apply adhesiveon the building at that predetermined location. In such an embodimentthe or each manipulator applies adhesive on horizontal and verticalsurfaces at the predetermined location.

However in an alternate embodiment of the automated brick laying systemthe brick laying and adhesive applying head may comprise first andsecond manipulators, each manipulator arranged to (a) grip and lay abrick at a predetermined position; and (b) apply adhesive for the brickto be laid.

The first manipulator may lay adhesive for a brick to be laid by thesecond manipulator, and the second manipulator may likewise applyadhesive for a brick to be laid by the first manipulator.

In one form of the automated brick laying system, the first and secondmanipulators apply adhesive at locations which, when a brick is laid,are between vertical faces of that laid brick and a previously laidbrick on the same course and a horizontal face of that laid brick and astructure on which the laid brick is supported. When the manipulatorsapply adhesive between the vertical faces, one of the manipulators mayapply a force to the brick being laid in a direction to compress theadhesive between vertical faces of the brick being laid and a previouslylaid brick. In this embodiment, the other manipulator may hold thepreviously laid brick while the compressive force is being applied.

The automated brick laying system may further comprise a conveyor systemthat transports individual bricks from a supply of bricks to the head.An automated brick loader may also be provided that automatically loadsbricks from the supply onto the conveyor system. In one embodiment, theconveyor system comprises one or more endless loop conveyors.

The automated brick laying system may further comprise a brick cuttingdevice to cut a brick to a shape required for laying at a predeterminedlocation in the building. The cutting device can take the form of a sawor a guillotine. The cutting device may be located upstream of theconveyor system.

However a further embodiment is envisaged that instead of the conveyorsystem the head may further comprises a brick carrying device which holda supply of bricks to be laid. The supply could for example be a palletof bricks.

In one embodiment of the automated brick laying system, the base islocated outside of a peripheral wall of the building to be constructed.The base may further comprise a plurality of jacks and/or a movablecounter weight that can be controlled by the controller. The movablesupport structure can comprise one of the group consisting of a scaraarm, a telescopic boom, a gantry or some other form of crane likestructure.

According to a further aspect of the present invention there is providedan automated brick laying system for constructing a building from aplurality of bricks comprising:

-   -   first and second manipulators wherein at least the first        manipulator is arranged to grip and lay a brick and at least the        second manipulator is arranged to lay adhesive for a brick        gripped by the first manipulator.

In this aspect of the invention each of the first and secondmanipulators may be arranged to (a) grip and lay a brick at apredetermined position; and (b) apply adhesive for the brick to be laid.Additionally the system may comprise a controller which controls thefirst and second manipulators to lay the bricks at respectivepredetermined locations in a sequence where a complete course of bricksis laid prior to the laying of a brick for a next course of bricks.

According to a further aspect of the invention there is provided anautomated brick laying system for constructing a building from aplurality of bricks comprising:

-   -   a brick laying robot provided with a moveable support structure        adapted to reach over an entire area of the building being        constructed and a brick laying and adhesive applying head        coupled to an end of the moveable support structure;    -   a measurement system which measures the position in real time of        the head and produces corresponding position data; and,        a controller which receives the position data and produces        control data on the basis of a comparison between the position        data and a stored predetermined position for the head to lay a        brick at a predetermined location for the building, the        controller controlling the moveable support structure to provide        coarse positioning of the head and controlling the or each        manipulator to provide fine positioning of the bricks.

In this aspect of the invention the controller may control the moveablesupport structure to move with a slow dynamic response and control theor each manipulator to move with a fast dynamic response.

According to a further aspect of the invention there is provided anautomated method of constructing a building from a plurality of brickscomprising:

-   -   providing a brick laying robot having a brick laying and        adhesive applying head;        measuring the position in real time of the head and producing        corresponding position data;        producing control data on the basis of a comparison between the        position data and a stored predetermined position for the head        to lay a brick at a predetermined location for the building;        and,        controlling the robot to lay the bricks at their respective        predetermined locations in a sequence where a complete course of        bricks is laid prior to the laying of a brick for a next course        of bricks.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described by way ofexample only with reference to the accompanying drawings in which:

FIG. 1 is a schematic representation of a brick laying robot for a firstembodiment of an automated brick laying system in accordance with thepresent invention;

FIG. 2 is a schematic representation of a brick laying robot for asecond embodiment of the automated brick laying system;

FIG. 3 is a schematic representation of a brick laying robot for a thirdembodiment of the automated brick laying system;

FIG. 4 is a schematic representation of a brick laying robot for afourth embodiment of the automated brick laying system;

FIG. 5 is a schematic representation of a brick laying robot for a fifthembodiment of the automated brick laying system;

FIG. 6 is a schematic representation of a brick loading systemincorporated in an embodiment of the automated brick laying system;

FIG. 7 is a general overview for the automated brick laying system;

FIG. 8 is a process flow diagram depicting one method of controlling abrick laying head of the brick laying robot;

FIG. 9 is a process flow diagram depicting an embodiment of one methodfor controlling a boom of the brick laying robot;

FIG. 10 is a process flow diagram showing a method of controlling a baseof the brick laying robot; and,

FIG. 11 is a schematic representation of a brick laying and adhesiveapplying head incorporated in a sixth embodiment of the brick layingsystem.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1 and 7 depict the substantive components for an embodiment of anautomated brick laying (ABL) system 10 in accordance with the presentinvention. In particular FIG. 1 depicts a brick laying robot 12,measuring system 13 and controller 14 for one embodiment of the ABLsystem 10, while FIG. 7 provides a general overview of the operations orfunctions performed by the ABL system 10. In a broad sense, the ABLsystem 10 for constructing a building from a plurality of bricks 16comprises the brick laying robot 12 provided with a brick laying andadhesive applying head 18, the measuring system 13 and the controller 14that provides control data to the robot 12 to lay the bricks 16 atpredetermined positions. The measuring system 13 measures in real timethe position of the head 18 and produces position data for thecontroller 14. The controller 14 produces control data on the basis of acomparison between the position data and a predetermined orper-programmed position of the head 18 to lay a brick 16 at apredetermined position for the building under construction. The robot12, under the control of the controller 14 applying the control data,constructs the building. A database 70 (shown in FIG. 7) holding thepredetermined positions for the brick and co-ordinate data for the robot12 may be formed in a manner so that the ABL system 10 constructs thebuilding course by course where the bricks 16 are laid sequentially attheir respective predetermined positions where a complete course ofbricks for the entire building is laid prior to laying of a brick forthe next course.

The measuring system 13 may incorporate a (or indeed a number of)automated total station (ATS) 20 and an associated target 21. Themeasurement system 13 provides real time position data relating to theposition in space of the head 18 and sends that position data to thecontroller 14, typically by a radio communication link, although ofcourse any type of communication link may be used.

The robot 12 comprises a combination of off-the-shelf components whichare known in the construction and/or robotic industries. With referenceto FIG. 1, the robot 12 comprises a base 22 in the form of a tractor orwheel based vehicle, a movable support structure in the form of a scaraarm 24 which is coupled at one end to the base 22, and at an oppositeend to the brick laying and adhesive applying head 18. The head 18comprises first and second manipulators 28 and 30. The manipulators cantake the form of numerous commercially available or speciallyconstructed robotic arms provided with a gripper. One example of such agripper is FESTO HGPT-63-A-G1 parallel gripper. An outlet of an adhesivedelivery system, such as, but not limited to a PUTZMEISTER MP25 mixitmixer pump is attached to each of the manipulators 28 and 30 for thedelivery of mortar which acts an adhesive when the building beingconstructed is made from masonry bricks. The scara arm 24 comprises afirst length 32 which is coupled at one end to the base 22, a secondlength 34 that is coupled at one end to the opposite end of length 32and a third length 36 that extends from an opposite arm of the secondlength 34 to the head 18. The first length 32 is coupled to an elevator38 of the base 22. The elevator 38 allows the entire arm 24 to betranslated in a vertical plane.

As will be understood by those skilled in the art, the length 32 iscoupled about a vertical pivot axis to the elevator 38, and the secondlength 34 is coupled at each of its opposite ends about respectivevertical pivot axis to the lengths 32 and 36. Thus the entire scara arm24 can fold and unfold in a horizontal plane by relative pivoting of thelengths 32, 34 and 36 about their respective vertical pivot axis. Inaddition, by virtue of the coupling of the arm 32 to the elevator 38,the entire scara arm 24 can be moved in a vertical plane. Each of themanipulators 28 and 30 may be provided with at least five or six degreesof freedom of movement.

A conveyor system 40 is provided along the scara arm 24 for transportingbricks 16 from a supply or stack of bricks (typically in the form of aplurality of pallets of bricks) to the head 26. The conveyor system 40comprises a plurality of individual endless loop conveyors 42, 44 and 46for each of the lengths 32, 34 and 36 of the scara arm. The conveyorsystem 40 delivers a brick to a known position at the head 18 so thatevery time a brick is delivered to the head 18 its precise position isknown relative to the head 18. Thus each time a brick is picked up by amanipulator 28 and 30 it is picked up in a known position relative tothat manipulator 28, 30.

As is apparent from FIG. 1, the ABL system 10 operates or is deployed onthe actual building site. Here, the site 48 is provided with a pre-laidfooting 50 on which the bricks 16 laid by the ABL system 10 aresupported. It will also be noted in this embodiment, the base 22 is onthe outside of a peripheral wall of the building to be constructed.However in alternate embodiments, particularly where a regular shapedlarge building such as a rectangular storage shed is being constructed,the base 22 may be located inside the peripheral wall. It is recognisedhowever that in the event of the base 22 being inside the peripheralwall, access must be provided in order to enable the base 22 to beremoved after construction of the building.

The base 22 includes various motors, pumps and compressors for example adiesel motor, hydraulic motor, electric motors, and air compressors toprovide appropriate power to the remaining components of the robot 12.The base 22 may also include an industrial controller or provide plugsand/or jacks to enable connection to an industrial controller to providecontrol signals to affect the required motions and actions of the robot12.

The measurement system 13 may also comprise an inertial navigationsystem 51 located near or adjacent to the target 21 on the head 18 orsupport structure/arm 24. The inertial navigation system 51 may be anyof a number of commercially available units that include accelerometersand gyros and a microprocessor that integrates the accelerations toprovide spatial position data to the controller 14. The inertialnavigation system data is used to provide a high bandwidth (ie highupdate rate) position data stream between readings from the lowbandwidth (ie low update rate) ATS 20. The high data rate is required bythe controller 14 to enable real time correction of structural dynamiceffects and deflection of the arm 24. Typically inertial navigationsystems suffer from position output drift error (ie error that increaseswith time). However with the frequent updating of actual position fromthe ATS 20 (typically 5 to 80 Hz) the effects of this problem can bereduced or eliminated.

Indeed it is envisaged that an alternate embodiment of the measurementsystem 13 may be possible where only the an inertial navigation system51 is used in conjunction with measurement of the relative position ofthe arm 24 via position encoders and static deflection estimation basedon look up tables or formula based on the position of boom componentsfor the purposes of determining the dynamic component of deflection ofthe arm 24.

FIG. 7 provides a general overview of the operation of the system 10. Atan initial step 52, architectural CAD drawings are provided as initialinput data to the system 10. The drawings are converted at step 54 to aseries of brick co-ordinates identifying the location of each brick inspace. The brick co-ordinates are then converted at step 56 to an ASCIIbrick location file.

Prior to the operation of the robot 12 to lay bricks, the controller 14performs a routine 60 to adjust, if necessary, the location file 56 totake account of the actual conditions on the building site 48 and inparticular the location and geometry of the footing 50 prior to thecommencement of construction. In order to perform the routine 60, themeasuring system 13, and in particular in this embodiment, the ATS 20 isset up to conduct a survey of the site 48. This is performed usingnormal surveying techniques. A radio link 62 transfers survey data fromthe ATS 20 via an ATS interface 64 and a communication bus 66 to thecontroller 14 which runs the routine 60. Upon running the routine 60 thecontroller modifies if necessary a database 70 containing co-ordinatedata the bricks to be laid and for the robot to lay the bricks 16. Theco-ordinate data for the robot may comprise data relating to the axisposition of joints of the arm 24 and manipulators 28 and 30, to lay abrick at a predetermined location in the building.

A human-machine interface (not shown) may be provided to allow operatorintervention such as selecting between two or more building designchanges required to take account of variations between a designedfooting/building location and the actual footing design and/or buildinglocation.

When onsite, the ATS 20 makes real time measurements of the position inspace of the head 18 by viewing the target 21 (see FIG. 1) at the end ofthe scara arm 24. Since the bricks delivered by the conveyor system 40are presented at a known location for gripping by the manipulators 28and 30, knowing the location of the head 18 also means that the positionof a brick to be gripped by the manipulators 28 and 30 is known.Further, given that the configuration of each of the grippers 28 and 30is known and their movements are controlled, the location of a brickheld by the grippers 28 and 30 is always known irrespective of themovement of the manipulators 28 and 30. Of course, as is common, themanipulators 28 and 30 are provided with position transducers such asrotary and linear encoders so that their position in space is known andcan be fed back to the controller 14.

The controller 14 runs a process 84 for controlling the laying head 18,and in particular the manipulators 28 and 30; a process 86 forcontrolling the position and motion of the scara arm 24; and a process88 for controlling the base 22. The signals for the control of the head18, scara arm 24 and base 22 are provided by the communication bus 66.

FIG. 8 depicts the main process flow steps for the process 84 shown inFIG. 7. The first step 92 in the process 84 is to load brick informationfrom the database 70. Next, at step 84, a decision is made as to whichof the manipulators 28 and 30 is to lay the next brick. From here, theroutine 84 splits into two mirror image subroutines, comprisingsubroutine 96 for the arm 28 and subroutine 98 for the arm 30.

In the following description only the subroutine for arm 96 will bedescribed in detail. At step 100 the arm 28 is provided with signalsinstructing it to pick up the next brick while at step 102 the arm 30 isin effect notified that it will be laying adhesive (e.g. mortar) for thenext brick to be laid. Following step 100, the controller 14 at step 104determines the position at which the brick, which was picked up by thearm 28, is to be laid. In determining this position, the step 104 isprovided with data on the real time position of the tip of the arm 24.This data is derived via step 106, which in turn is derived from the ATS20. The position data provided by step 106 is continuously updatedtaking into account the movement of the robot 12 during the brick layingprocess. When determining the position of the brick to be laid in orderto control the motion of the robot 12 and in particular the manipulators28 and 30, the controller 14, in constructing the control data, takesinto account the information derived from the database 70, the real timeposition of the head 18, and a predicted position of the brick held by amanipulator 28, 30 in the period between real time position measurementstaken by the measurement system 13. More particularly the controller 14compares the measured position of the head 18 and compares that with anexpected position of the head 18 stored in database 70 for a brick to belaid at a predetermined or pre-programmed position. If these positionsmatch or are within an acceptable range then the control data used orproduced by the controller 14 corresponds with the robot co-ordinatedata in database 70. If these positions do not match and are not withinan acceptable range, (for example due to wind loading or deflection ofthe arm 24) the controller modifies the robot co-ordinate to produce thecontrol data to ensure that brick is laid at its predetermined positionin the building.

At step 106, following the step 102, the controller also determines theposition of the manipulator 30 for the purposes of applying the mortar.The process here is in essence identical to the process at step 104 andutilises as an input the position data derived from step 106.

Following step 108, the arm 30 is controlled at step 110 to place mortarat a location to receive the brick to be laid by the arm 28. Typically,the mortar will be placed on a vertical face of a previously laid brickon the same course, and half of the horizontal face of two adjacentbricks on an underlying course. (Naturally, in the event of the firstcourse being laid, then the application of the horizontal bed of mortarwill be simply on the footing rather than on any bricks laid course ofbricks).

After the arm 30 has laid its mortar, a determination is made at step112 as to whether a previously laid brick requires to be held. This willoccur for example where the previously laid brick is at a corner or atan end of a wall. When mortar is applied between vertical faces ofadjacent bricks, the manipulator laying the next brick to applies acompressive force on the mortar between the vertical faces. This forcemay move or dislodge a previously laid brick if that brick is not held.It may be a requirement that the first few bricks following a corner orend of a wall require to be held while a brick is being laid.

However it is also envisaged that in buildings where mortar or adhesiveis not applied to vertical faces, for example where bricks withinterlocking vertical faces are used, there may be no need to hold apreviously laid brick. In the event that at step 112 it is determinedthat a previously laid brick requires to be held then the controller 14at step 114 controls the manipulator 30 to hold the previously laidbrick. Meanwhile, at step 116, the manipulator 28 is controlled to laythe next brick. The laying of the brick is sensed and the brick locationfiled at step 92 is updated to provide the position information for thenext brick to be laid.

Irrespective of whether the manipulator 30 during the laying processheld, or was not required to hold, the previously laid brick, at step118 the manipulator 30 is driven to a position to pick up the next brickto be laid. Thereafter, the routine repeats itself but in a mirror imagefollowing the subroutine 98 and mirrored steps 100 m-118 m. Thus the armthat previously laid a brick now becomes the arm that lays the mortarwhile the arm that previously laid the mortar becomes the arm that laysthe next brick.

FIG. 9 depicts the main processes in the support structure positioningroutine 86 referred to in FIG. 7. The routine commences at step 130where the database 70 is accessed to obtain the location required forthe head 18 to lay the next brick. At step 132 the controller haltsmovement of the arm 24 and head 18 if the location derived at step 130indicates that a change in the height of the arm 24 and head 18 isrequired to lay a new course of bricks, in which case a further routineadjusts their height by, for example in FIG. 1, operating the elevator38 to lift the entire structure of the arm 24 and head 18 in thevertical plane. However in alternate embodiments, as will be describedin greater detail hereinafter, this may be achieved by the operation ofjacks to lift the base 22.

At step 134 the routine 86 accesses a function block used forcontrolling motion of the arm 24 this function block calculates apreferred motion of the arm 24 to move between two points. In thisregard, it should be recognised that given the multiple pivot axis forthe lengths 32, 34 and 36 the lengths may be individually moved in anumber of different ways in order for the tip of the arm, ie the head18, to be moved to a particular position. Step 134 determines the mostefficient motions of the individual lengths 32,34,36 to achieve thedesired position of the head 18.

At step 138, the controller 14 initiates movement of the arm 24. Next atstep 140 the position data from the measurement system 13 is called inorder to determine the position of the end of the arm 24 (whichcorresponds with the position of the head 18). Subsequently at step 150a test is made to determine whether the tip of the arm 24 is at alocation within a desired range or region for the laying of the nextbrick. For example, it may be desired to locate the tip of the arm 24,i.e. the head 18 within an imaginary sphere having a radius of 100 mmfrom the required laying location. Thus in effect, the routine 86provides a “coarse control” for the position of the laying of the nextbrick. “Fine control” of the robot 12 for the positioning of the brickto be laid is achieved by the previously described routine 84 depictedin FIGS. 7 and 8. More particularly the support structure, which in FIG.1 is embodied by the arm 24, is controlled to cover relatively largedistances but with relatively low positional accuracy and slow dynamicresponse. In contrast the head 18, and moreover the manipulators 28 and30, are controlled to cover smaller distances but with high positionalaccuracy and fast dynamic response, and in a manner that corrects forany deflection or positional error of the support structure.

If at step 150 it is determined that the boom is within a predeterminedrange of locations then at step 152 a pointer is incremented in thedatabase 74 to point to the next position and space required for the tipof the arm 24/head 18 in order to lay the next brick. The routine thenrecommences at step 130. The routine 86 may indeed hold the arm 24 at aparticular location while several bricks are being laid if the tip ofthe arm 24 is determined at step 150 to be within a predetermined rangefor the laying of the next brick.

The base control process 88 depicted in FIG. 7 is shown in greaterdetail in FIG. 10. The process 88 commences at step 160 where a set uproutine is called for the base 22. This routine involves placing thebase 22 at a particular location on the site 48 and measuring thatlocation together with the vertical position of the arm 24 and head 18.Next at step 162, information regarding the location of the next brickto be laid is loaded from the database 72. At step 164 a determinationis made as to whether the brick to be laid is, on the same course as theprevious brick or, the first brick in a next course. If the brick is thefirst brick in the next course then at step 166, the current centre ofgravity and weight distribution of the robot 12 is calculated. In orderto perform this calculation, the location of the tip of the arm 24 isderived at step 168 using the ATS 20 and provided as an input to thestep 166. The information derived from step 168 is also provided as aninput to step 170 which is the step that the process 88 progresses to inthe event that at step 164 it is determined that the brick to be laid ison the same course as the previously laid brick.

Following step 166, a routine 172 is deployed to vertically lift the arm24 in order to lay the next course of bricks. Depending on the type ofbase 22, this can be achieved by either operating the elevator 38 toincrement the vertical position of the arm 24, or if the base 22 isprovided with ground engaging jacks, this process may involve operatingthe jacks to lift the base and thus the arm 24. During this processaccount is taken of the centre of gravity for the entire robot 12 whichof course will change with the lifting of the arm 24 and/or base 22.

At step 174, using information from steps 170 and 172 as inputs, thefootprint of the base 22 is dynamically balanced. This may involve themovement of counter weights and/or the operation of jacks orstabilizers. Finally, at step 176, further adjustment is made to thebase 22 to take account of skew, twist and tilt at the end of the arm24.

The positioning system 14 depicted in FIGS. 7-10 can be used within avariety of different types of robots 12. FIG. 2 depicts an alternateform of robot 12 a which performs the same functions as a robot 12 shownin FIG. 1 but with the scara arm 24 replaced by a telescopic boom 24 a.A head 18 a is coupled to the end of the boom 24 a distant the vehicle22 a, and is provided with manipulators 28 and 30 similar to thatdepicted in FIG. 1.

FIG. 3 depicts in a further variation of the robot 12 b which comprisesa track based vehicle 22 b provided with a composite boom 24 bcomprising a first articulated length 32 b and a second articulatedlength 34 b, where the length 34 b comprises a telescopic arm. A head 18b similar to the head 18 shown in FIG. 1 is provided at the end of thelength 24 b.

FIG. 4 depicts a further variation of the robot 12 c in which the base22 c is in form of a platform supported on a plurality of jacks 23 and agantry 24 c in place of the scara arm, which supports a head 18 csimilar in construction and operation to the head 18 of FIG. 1.

FIG. 5 depicts in a further variation of the robot 12 d where thesupport structure is in the form of a tower crane to which the head 18 dof similar construction to the head 18 is coupled. Also in thisembodiment the conveyor system 40 comprises a brick elevator 40 d whichcarries a supply of bricks to the head 18 d.

FIG. 6 is a schematic representation of a brick loading systemincorporated in the automated brick laying system 10. The brick loadingsystem 200 comprises a robotic arm 202 having a gripping mechanism 204at one end that can grip a row of bricks. The robotic arm 202 places thebricks on a conveyer 206 which passes through a brick cutting device208. The brick cutting device 208 is under the control of thepositioning system 14 and operates to cut a brick if required.Information pertaining to whether or not a brick is to be cut isobtained from the brick location database 72. Bricks are cut inaccordance with the laying sequence of bricks. The cutting of the bricksmay be achieved by use of a guillotine or a saw. The bricks exiting thecutter 24 are transferred by a further robotic arm 210 onto theconveying system 40. Thus, the cutting is performed upstream ofconveying system 40.

In order to enhance the safety, a perimeter light curtain may be set upto prevent unauthorized access to the building site 48. If the lightcurtain is tripped motion of robot 12 is halted. It is further envisagedthat the system 10 may require only a single operator. The operator maybe provided with a RF transponder or identification badge that isrecognized by the system 10 and can be sensed by sensors mounted on thehead 18. If the operator wearing the badge is sensed to be within adangerous distance of the sensor, the robot is halted.

It would be appreciated from the above description that in embodimentsof the present invention, the system 10 provides accurate laying ofbricks by measuring and taking account of deflection in the arm/supportstructure 24 due to gravity, wind and dynamic response (i.e. the motionof the boom itself). Door and window frames, lintels and other buildingelements that are required in the building being construction, aresimply dropped or inserted into place by the operator prior to thelaying of the course of bricks immediately above such element. To thisend the database 70 contains information on the position of door,windows and other openings and halts the laying of bricks automaticallyto allow such elements to be dropped into spaces which were left in thewalls being constructed. The ABL system 10 may also provide an audioand/or visual message alerting the operator of the need to insert therequired building elements. To this end in one possible embodiment themanipulators 28 and 30 can be fitted with optical proximity sensors toascertain the exact location of gripped brick and use such sensors tocheck that the lintel, doorframe or other component has been placed. Thecontroller 14 can be provided with a “check item has been placed”subroutine that essentially moves the gripper (without a brick) over theitem so that the proximity sensor can detect its presence, if there isno item, the operator is alerted, if the item is there the programcontinues.

In the embodiments shown in FIGS. 1-6 a conveyor system 40 is depictedfor transferring bricks 16 from a supply to the head 18. However asshown in FIG. 11, in an alternate arrangement the conveyor system 40 canbe replaced by a brick carrying device 40 a incorporated in the head 18.The device 40 a holds and a supply of bricks which the manipulators cangrip. This embodiment also shows a further variation where the headcomprises a single manipulator 28 rather than two manipulators.Nevertheless, it will be appreciated that two or more manipulators canbe used with the brick carrier device 40 a.

Now that embodiments of the invention have been described in detail itwill be apparent to those skilled in the ordinary arts that numerousmodifications and variations may be made without departing from thebasic inventive concepts. For example in the described embodiments, thehead 18 is depicted as comprising two robotic arms or manipulators 28and 30. However the head 18 may be provided with only a singlemanipulator or alternately may be provided with more than twomanipulators. Further, the described embodiments employ an automatictotal station 20 for position measuring. However other types of positionmeasuring systems may be used in place of, or in combination with, theATS 20 such as differential GPS combined with a scanning laser toprovide a vertical position measure; and/or the use of strain gauges toprovide measurement data on the deflection of the boom. All suchmodifications and variations together with others that would be obviousto a person skilled in the art are deemed to be within the scope of thepresent invention in the nature of which is to be determined from theabove description and the amended claims.

1. An automated brick laying system for constructing a building from aplurality of bricks comprising: a brick laying robot provided with abase coupled at one end to a moveable support structure and a bricklaying and adhesive applying head coupled to an opposite end of themoveable support structure, the head comprising at least one manipulatoroperable to lay bricks; a measurement system which measures the positionin real time of the head and produces corresponding position data,wherein the measurement system includes a non-contact opticalline-of-sight position measuring system remotely located away from saidbase to view a target located on the opposite end of the moveablesupport structure; and a controller which receives the position data andproduces control data on the basis of a comparison between the positiondata and a stored predetermined position for the head to lay a brick ata predetermined location for the building, the controller controllingthe moveable support structure to provide coarse positioning of the headand controlling the at least one manipulator to provide fine positioningof the bricks, wherein the fine positioning provides finer positioningthan the coarse positioning, and wherein the controller controls themoveable support structure to move with a slow dynamic response, andcontrols the at least one manipulator to move with a fast dynamicresponse to compensate for structural dynamic effects and deflection ofsaid moveable support structure, wherein the fast dynamic response isfaster than the slow dynamic response.
 2. The automated brick layingsystem according to claim 1 wherein the automated total station and/orthe scanning laser measures the position in real time of the head with alow update rate of data of from 5 to 80 Hz, and the measurement systemalso measures the position in real time of the head at a high dataupdate rate to enable real time correction of structural dynamic effectsand deflection.
 3. The automated brick laying system according to claim2 wherein the measurement system comprises an inertial navigation systemto measure the position in real time of the head at a high data updaterate, that provides data relating to the location in space of the headto the controller.
 4. The automated brick laying system according toclaim 1 wherein the measurement system comprises a scanning laser toprovide location data relating to the real time position of a brick heldby the head, wherein the measurement system uses the location data toproduce the position data.
 5. The automated brick laying systemaccording to claim 1 wherein the controller controls the head to lay thebricks at respective predetermined locations in a sequence where acomplete course of bricks is laid prior to the laying of a brick for anext course of bricks.
 6. The automated brick laying system according toclaim 1 wherein the head comprises at least one manipulator arranged togrip and lay a brick at its predetermined location and apply adhesive onthe building at that predetermined location.
 7. The automated bricklaying system according to claim 6 wherein the or each manipulatorapplies adhesive on horizontal and vertical surfaces at thepredetermined location.
 8. The automated brick laying system accordingto claim 5 wherein the head comprises first and second manipulators,each manipulator arranged to (a) grip and lay a brick at a predeterminedposition; and (b) apply adhesive for the brick to be laid.
 9. Theautomated brick laying system according to claim 8 wherein firstmanipulator applies adhesive for a brick to be laid by the secondmanipulator, and the second manipulator applies adhesive for a brick tobe laid by the first manipulator.
 10. The automated brick laying systemaccording to claim 8 wherein, the first and second manipulators applyadhesive at locations which, when a brick is laid, are between verticalfaces of that laid brick and a previously laid brick on the same courseand a horizontal face of that laid brick and a structure on which thelaid brick is supported.
 11. The automated brick laying system accordingto claim 10 wherein, when the manipulators apply adhesive between thevertical faces, one of the manipulators applies a force to the brickbeing laid in a direction to compress the adhesive between verticalfaces of the brick being laid and a previously laid brick.
 12. Theautomated brick laying system according to claim 11 wherein, an other ofthe manipulators holds the previously laid brick while the compressiveforce is being applied.
 13. The automated brick laying system accordingto claim 1 further comprising a conveyor system that transportsindividual bricks from a supply of bricks to the head.
 14. The automatedbrick laying system according to claim 13 further comprising a brickloader that loads bricks from the supply onto the conveyor system. 15.The automated brick laying system according to claim 13 wherein theconveyor system comprises one or more endless loop conveyors.
 16. Theautomated brick laying system according to claim 1 wherein the headfurther comprises a brick carrying device which hold a supply of bricksto be laid.
 17. The automated brick laying system according to claim 1further comprising a brick cutting device to cut a brick to a shaperequired for laying at a predetermined location in the building.
 18. Theautomated brick laying system according to claim 17 wherein the cuttingdevice comprises a saw or a guillotine.
 19. The automated brick layingsystem according to claim 17 wherein the cutting device is locateddistant the head.
 20. The automated brick laying system according toclaim 1 wherein the robot further comprises a ground engaging base towhich the support structure is coupled, and wherein the controllercontrols the position of the base on the basis of the control data. 21.The automated brick laying system according to claim 20 wherein thecontroller controls the position of the base to maintain the position ofthe head in a datum plane for a particular course being laid.
 22. Theautomated brick laying system according to claim 21 wherein the basefurther comprises one or both of (a) a moveable counterweight and (b)one or more jacks; and wherein the controller controls the position ofthe base by effecting a movement of the counterweight and/or deploymentof one or more the jacks to counteract a bending or twisting momentapplied by the support structure to the base.
 23. The automated bricklaying system according to claim 1 wherein the movable support structurecomprise one of the group consisting of a scara arm, a telescopic boom,a gantry or other crane like structure.
 24. The automated brick layingsystem according to claim 1 wherein the moveable support structure isadapted to reach over an entire area of the building being constructed.25. The automated brick laying system according to claim 1 wherein thenon-contact optical line-of-sight position measuring system is selectedfrom an automated total station, a scanning laser, and a combination ofthe automated total station and the scanning laser.